Thermostat



llt

Patented Oct. 27, 1925.

UNITED STATES PATENT orificeD ROY J. WENSLEY, OF EDGEWOOD HARK, PENNSYLVANIA, ASSIG'NOR TO WEST'i'G HOUSE ELECTRIC MANUFACTURING COMPANY, A COEPORATON OF PENNSYL- VANIA.

THERMOSTAT.

Application tiled December 10, 1819. Serial No. 343,977.

To ol( l/zom if moj/ concern:

lie it known that l. Roi' J. VVENSLEY, a citizen ot the United States, and a resident ot Edgewood Park. in the county of Allegheny and State of Pennsylvania. have invented a new and useful Improvement in '.llieriuost'ats, of which the following is a specitication.

My invention relates to protective. thermostats and it has special relation to thermostats employed for protecting machine `parts. More particularly` my invention relates to means Vtor protecting the bearings of electrical machinery, suchl as generators and motors. although I wish it expressly understood thatI its use is not limited to this class o'l machinery `but is applicable to the protection of all machine parts where friction occurs.

ln the past. as a rule. it. 'as ditlicult'to determine when a hearing heeame overheated and. in many ii stances. the heating reached such a high dgrec ot temperature that the hearing metaistarted to flow, thus ruining the hearing. This condition often obtained even though the machinery was in charge ot an attendant. and. in cases where the unichineswere inspected onl Y .at infrequent' intervals. great damage and even wrecking ot the planty might occur. hecause of the continued ruiming otl a machine after the hearing metal had heen melted. 'lo

atlol'd exemption trom damage ot this kind,

as a result ot' the overheating oi hearing surtaces` this invention was conceived.

;\n object ot my invention is to provide means for cuting otil the power from rotating machinery when the hearings start to overheat. and it. is especially appli Vahle for providing a sure and automatic means for shuttingl down an automatic substation when the hea rings ot the rotary converter` r motfir-generator set hecome overheatedlt,

With these and other objects in viewdthe invention consists in the parts and the cpmhinations thereof hereinafter 'set forth :and claimed` with the understainling that tithe, several necessary elements i constituting tthe, same may he, varied in proportions andtarrangement without departing from the `spirit and scope of the invention.

Vln order to make the invention more cleartv understood, I show, in the accompanying drawings, means tor carrying the same intto vertical ett'eizt, without limiting the im In the drawings, Va bearing 1 is lined with Babbitt or other suitable hearing metal 2 in which a shaft 3 is adapted to turn. ln close proximity to the lining 2 and insertedin an opening 4 in the housinfY of the bearing 1. is a thermally conductive hulh 5 ot metal or any other suitable material. filled or partially filled with a volatile fluid, not indicated in the drawings.

A tube 6 extends upwardly Jfrom the hulh 5 and is protected from injury, over a portion of its length in proximity to the hearing 1, by a support 7 in the form ot a hollow metal member, screwed, at 8. into the housing ot the hearing 1. A metal caf, t.

that is provided with anv aperture 10 tlirough which the tuhe 6 projects, is disposed atl the end ot the support 7 remote from the hear ing 1. To ensure a close fit, the inner surface o'f the cap 9 is provided with a disk of cork or other suitable packing material. as indicated aty 11. To hold the cap f) and the cork disk 11 in place. the support 7 is screw-threaded at the end upon which the cap t) is disposed and a screw-threaded cap 12` having a central aperture 13 forthe passage ot the tube 6 therethrough, is screwed vover the tirst mentioned cap.

A bent metal rod 14 is bolted to the housing ot the bearing 1 and supports a housing lladjacent to the upper end of its vertical portion, within which are contained a mevtallic bellows and a circuit-breaking device.

The bellows 16 is provided with a neck 17 which projects through the side ot' the housing 15 and through a suitably provided .aperture formed in the support 14. The outer end ot the, neck 1T is screw threaded to receive a screw-cap 13 through which the 'ruhe` 6 communicates with the bellows, and which firmly clamps the support 14 and the bellows 16 to the housing 15.

A. projection 19 is disposed on the end of the bellows opposite the neck 17, and an insulating tube 2O is screw threaded co-*such rejection to serve as a guide'for an insulating rod 21. The. rod 21 engages the end of the projection 19 but is no t secured thereto,

fili

thereby providing a lost-motion connection with the rod Vwhen the bellows is contracting and when the rod is held in position, as hereinafter set forth. On the rod-2l and itbin the housing l5 is located a collar 23 oany usitable conducting material. One oi? the rod 2l projects through an annu lar aperture 24a in the end of the housing and .is provided with a collar 2l, to limit the degree et movement ot the rod inwardly; The aperture 2l-(r. is of sulicient size to per. mit the, interior-otl the housing l5 to remain constantly; at atmospheric pressure.

'lfwr'i binding posts Q5- and 26 are mounted in the end ot the housingq and are pro- 'rided with heads 2? and 28, respectively, iter clamping spring contact 'members 39 and 3U in position to eltect engagement with the rod 2l. l

ln operation. when the bearing l becomes overheated, the volatile liquid in the bulb 5 is partially `Vapor-ized and produces vapor pressure in the tube 3 that iscomnuinicatcd to the metallic bellows lll. thus causing it to expand'. As a consequence` the rod 9i. moved against the frictioual contact spring contact members QS) and Si). temperature of the bearing rises enough to be dangerous to themachiue, Y 1c collar 23 on the rod Q1 will be 'forced etween the sprino' contact members 29 and 3() by means oit the extension ll) pressing; against the end oi the rod 2l. and a circuit through the collar 23 will beconipleted to cause an electro-magnetically conti-@lied eircuxt interruptor 31, ot' the usual i"type,v to' Open and tberclq7 disconnett all power from 'the machine 52. lt will be apparent that is impossible to again start the machine7 eren after the temperature ot the overheated parts has fallen lo normal, without resetting the thermal protector by hand.

Nomea .fis the rod 2l is not connected to the projection 19, the pressure ot .the spring' contac-t members on the collar 23 is suliicieut to prevent the rod from returning to its original position, after the vapor pressure has again fallen to normal. To permit the machine to be again set in motion, it is necessary to press the rod inwardly to disconnect the colla-r 23 from the Contact members 85) and 30 before the interrupter .3l is closed.

Although l. have Shown and described my invention asapplied to a Specific structure,

such as a bearingyprotecting thermostat, it is evident that it may be applied to many other types ot apparatus, and that various modification may be made therein without Vdeparting trom the spirit and scope ot the rod. and means on the rod for ernnpletingr.

an electrical circuit'tlirougb the Contact memliers.

2. A thermal protective device for bearings comprising' a bulb containingT a rolatile fluid, a bellous connected with the bulb and responsive only to the volatilizod fluid, an insulatingr rod operable by said l ello\\'s. contact members bearing against said rod, andv a collar on said rod adapted lo be forced between said contact members lo complete the electrical circuit threugh the contact members. i

ln test imony whereof, l have hereunto subscribed my name this 29th day oll Novem-- ber, i919. 

